Reflow soldering apparatus having independently openable main bodies

ABSTRACT

A soldering apparatus includes transfer rails as a first transfer means for transferring a printed circuit board, transfer rails as a second transfer means provided in parallel to a transfer direction of the printed circuit board to be transferred by the transfer rails, a muffle as a first reflow furnace main body for heating the printed circuit board transferred by the transfer rails, a muffle as a second reflow furnace main body for heating a printed circuit board transferred by the transfer rails, and a main frame as a frame for housing the muffle and the muffle. The main frame includes an opening/closing part as a first opening/closing means for opening/closing the muffle, and an opening/closing part as a second opening/closing means for opening/closing the muffle.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is the United States national phase of International Application No. PCT/JP2018/017,709 filed May 8, 2018, and claims priority to Japanese Patent Application No. 2017-111041 filed Jun. 5, 2017, the disclosures of which are hereby incorporated by reference in their entirety.

TECHNICAL FIELD

The present invention relates to a soldering apparatus for bonding an electronic component(s) onto a printed circuit board.

BACKGROUND

A reflow device has been generally used as an example of a soldering apparatus for soldering an electronic component(s) onto a printed circuit board. The reflow device includes a transfer means for transferring the printed circuit board, and the inside of the reflow device is divided into a preheating zone, a main heating zone, a cooling zone, and the like from the upstream of a transfer direction of the printed circuit board. Paste solder is printed on the printed circuit board in advance, an electronic component(s) is (are) mounted on this printed circuit board and they are heated by the reflow device to solder the electronic component(s) onto the printed circuit board.

Patent Documents 1 and 2 respectively disclose reflow devices in each of which a plurality of transfer means is arranged in parallel in a reflow furnace to improve the efficiency of soldering and shielding means is provided between the respective transfer means.

-   Patent Document 1: Japanese Patent Application Publication No.     2014-170906 -   Patent Document 2: Japanese Patent No. 5463129

SUMMARY OF THE INVENTION

However, the reflow devices of Patent Documents 1 and 2 have such a configuration that, when the reflow furnace main body is opened, the plurality of transfer means and various zones such as a preheating zone, a main heating zone and a cooling zone, which operate with respect to the printed circuit boards to be transferred by the respective transfer means, are exposed. Therefore, even when it is desired, for example, to maintain one transfer means side of the reflow furnace main body, it has been necessary to stop the drives of the other transfer means and/or the respective zones. Further, they have such a problem that, by opening the reflow furnace main body, the inside of the reflow furnace main body is exposed to the outside air, and the temperature of each of the zones in which heat is applied to the printed circuit board transferred by each of the transfer means is changed.

Therefore, the present invention solves such a problem, and an object thereof is to provide a soldering apparatus, in which transfer means are arranged in parallel, for preventing, even when the one transfer means side of a reflow furnace main body is opened, the inside of the reflow furnace main body on the other transfer means side from being exposed.

The technical means of the present invention adopted to solve the above-described problem are as follows.

(1) A soldering apparatus includes first transfer means for transferring a printed circuit board, second transfer means provided in parallel to a transfer direction of the printed circuit board transferred by the first transfer means, a first reflow furnace main body for heating the printed circuit board transferred by the first transfer means, a second reflow furnace main body for heating a printed circuit board transferred by the second transfer means, and a frame for housing the first reflow furnace main body and the second reflow furnace main body, wherein the frame contains first opening/closing means for opening/closing the first reflow furnace main body and second opening/closing means for opening/closing the second reflow furnace main body.

(2) The soldering apparatus according to the above item (1), wherein each of the first and second reflow furnace main bodies is configured to have an upper main body and a lower main body, wherein the first opening/closing means includes first lifting/lowering means for lifting/lowering the upper main body of the first reflow furnace main body, and wherein the second opening/closing means includes second lifting/lowering means for lifting/lowering the upper main body of the second reflow furnace main body.

(3) The soldering apparatus according to the above item (2), wherein the first lifting/lowering means is arranged while avoiding the first transfer means, and wherein the second lifting/lowering means is arranged while avoiding the second transfer means.

(4) The soldering apparatus according to the above item (2) or (3), wherein the first lifting/lowering means and the second lifting/lowering means include multistage cylinders.

(5) The soldering apparatus according to any one of the above items (2) to (4), wherein the lower main body of the first reflow furnace main body is provided with an elastic member at a position where the elastic member is sandwiched between the upper main body and the lower main body of the first reflow furnace main body and is in contact with them, and wherein the lower main body of the second reflow furnace main body is provided with an elastic member at a position where the elastic member is sandwiched between the upper main body and the lower main body of the second reflow furnace main body and is in contact with them.

(6) The soldering apparatus according to any one of the above items (2) to (5), wherein the first opening/closing means includes a first upper cover that covers an upper side and a lateral side of the upper main body of the first reflow furnace main body, wherein the second opening/closing means includes a second upper cover that covers an upper side and a lateral side of the upper main body of the second reflow furnace main body, and wherein the frame has an upstream side intrusion-preventing plate that is erected from the frame on an upstream side of the first upper cover and the second upper cover with respect to a transfer direction of any of the printed circuit boards and a downstream side intrusion-preventing plate that is erected from the frame on a downstream side of the first upper cover and the second upper cover with respect to the transfer direction of any of the printed circuit boards.

(7) The soldering apparatus according to any one of the above items (1) to (6), wherein an upstream end and a downstream end of the first transfer means along the transfer direction of the printed circuit board are provided on the frame, and wherein an upstream end and a downstream end of the second transfer means along the transfer direction of the printed circuit board are also provided on the frame.

(8) The soldering apparatus according to any one of the above items (1) to (7), wherein a heat-insulating member is provided around the first reflow furnace main body and the second reflow furnace main body.

(9) The soldering apparatus according to any one of the above items (1) to (8), wherein the first reflow furnace main body and the second reflow furnace main body respectively include a preheating zone for preheating the printed circuit board, a main heating zone for soldering the preheated printed circuit board, and a cooling zone for cooling the soldered printed circuit board.

The soldering apparatus according to the present invention includes a first opening/closing means for opening/closing the first reflow furnace main body and a second opening/closing means for opening/closing the second reflow furnace main body. Accordingly, the first reflow furnace main body and the second reflow furnace main body can be opened/closed separately. Furthermore, it is possible to set mutually different independent temperature profiles for soldering the printed circuit boards to the first reflow furnace main body and the second reflow furnace main body. Therefore, even when the one reflow furnace main body is opened, the inside of the other reflow furnace main body can be prevented from being exposed, and the other reflow furnace main body can keep the set temperature profile, while avoiding the temperature interference by the one reflow furnace main body.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partially exploded view of a soldering apparatus 100 according to the present invention for showing a configuration example thereof.

FIG. 2 is a schematic sectional view of the soldering apparatus 100 for showing a configuration example thereof as viewed from the arrow A1 direction in FIG. 1.

FIG. 3 is a schematic sectional view of a main frame 10, transfer rails 13A, 13B, cylinders 31A, 31B, and a rail width adjustment part 41A, taken along the lines A2-A2 in FIG. 2, for showing a configuration example thereof.

FIG. 4 is a partially exploded view of the soldering apparatus 100 for showing a configuration example thereof.

FIG. 5A is a schematic sectional view of the transfer rails 13A, 13B, muffles 20A, 20B and opening/closing parts 30A, 30B, taken along the lines A3-A3 in FIG. 4, for showing a configuration example thereof while the muffle 20A is opened.

FIG. 5B is a side view of the transfer rails 13A, 13B, the muffles 20A, 20B and the opening/closing parts 30A, 30B for showing a configuration example thereof while the muffle 20A is opened.

FIG. 6 is a block diagram of the soldering apparatus 100 for showing a control system thereof.

FIG. 7 is an explanatory view of the cylinders 31A, 31B and 31C for showing an operation example thereof.

DETAILED DESCRIPTION

There will describe a configuration of a soldering apparatus 100 as an embodiment according to the present invention with reference to the drawings. The soldering apparatus 100 is configured to solder printed circuit boards P1, P2 on each of which a surface mounting component(s) such as a power device is (are) mounted, for example. Hereinafter, the term “upstream” means an upstream side along a transfer direction of any of the printed circuit boards P1, P2, and represents a side of a board-charging port 11 for transferring the printed circuit boards P1, P2, shown in FIG. 2, into the soldering apparatus 100. Further, the term “downstream” means a downstream side along the transfer direction of any of the printed circuit boards P1, P2, and represents a side of a board carrying-out port 12 for transferring the printed circuit boards P1, P2 out of the soldering apparatus 100.

[Overall Configuration of Soldering Apparatus 100]

FIG. 1 is a partially exploded view of the soldering apparatus 100 as viewed from the upstream side. The soldering apparatus 100 includes transfer rails 13A as a first transfer means for transferring the printed circuit board P1, transfer rails 13B as a second transfer means for transferring the printed circuit board P2, a muffle 20A as a first reflow furnace main body for heating the printed circuit board P1, a muffle 20B as a second reflow furnace main body for heating the printed circuit board P2, and a main frame 10 as a frame for housing the muffles 20A, 20B. The main frame 10 includes an opening/closing part 30A as a first opening/closing means for opening/closing the muffle 20A, and an opening/closing part 30B as a second opening/closing means for opening/closing the muffle 20B. The transfer rails 13B are provided in parallel to the transfer rails 13A along the transfer direction of the printed circuit board P1. The main frame 10 includes, at its inside, a control unit 70 as shown in FIG. 6 which controls the operation of each unit.

As shown in FIG. 2, the main frame 10 is a case having a board-charging port 11 at its upstream end for transferring the printed circuit boards P1, P2 into the main frame 10, and having a board carrying-out port 12 at its downstream end for transferring the printed circuit boards P1, P2 out of the main frame 10. In the main frame 10, a plurality of rooms (zones) divided in series in the transfer direction of the printed circuit boards P1, P2 are provided. For example, a board-charging unit 14, a preheating zone 17 consisting of four zones I to IV, a main heating zone 18 consisting of one zone, a cooling zone 19, and a board carrying-out part 16 are arranged in this order from the upstream side to the downstream side along the transfer direction of the printed circuit boards P1, P2. Among them, the preheating zone 17, the main heating zone 18 and the cooling zone 19 are respectively provided in the muffle 20A, 20B. In the present embodiment, however, the zones on the muffle 20A side and the muffle 20B side will be collectively described below so that the zone configurations in the muffle 20A and the muffle 20B are the same.

The preheating zone 17 has heaters 7 for preheating the printed circuit boards P1, P2 to a predetermined temperature, which are provided oppositely in a vertical direction of the transfer rails 13A, 13B. The preheating zone 17 is preferably intended to raise the heating temperature of the printed circuit boards P1, P2 stepwise. The preheating zone 17 may have a plurality of preheating zones having different heating temperatures. For example, when it is desired to cause the printed circuit boards P1, P2 to reach 180° C., four preheating zones I to IV are provided, and the heating temperature of the heaters 7 in each preheating zone may be set to 150° C., 160° C., 170° C. and 180° C. In each of the zones I to IV in the preheating zone 17 of this embodiment, the gas (hot air) heated by the heaters 7 is blown to the printed circuit boards P1, P2 by a fan to heat the printed circuit boards P1, P2.

The main heating zone 18 is intended to solder the printed circuit boards P1, P2 preheated in the preheating zone 17. The main heating zone 18 has heaters 8 for heating the solder to a temperature equal to or higher than its melting temperature, the heaters 8 being provided oppositely in the vertical direction of the transfer rails 13A, 13B. The heaters 8 are set to a heating temperature of about 250° C. as an example.

The cooling zone 19 has cooling fans 9, as an example of a cold air blower for cooling the heated and soldered printed circuit boards P1, P2, the cooling fans 9 being provided oppositely in the vertical direction of the transfer rails 13A, 13B. In this embodiment, the cooling fans 9 are ON- or OFF-controlled only, but the operator may arbitrarily set the cooling time in accordance with the product. Further, temperature control may be performed using means such as a chiller so as to cool the printed circuit boards P1, P2 to a predetermined temperature. Also in this case, the operator can arbitrarily set the cooling temperature.

As shown in FIG. 3, the main frame 10 is provided with lower inner frames 10B which are located at a position sandwiching the transfer rails 13A and a position sandwiching the transfer rails 13B, on the inner side with respect to a lower outer frame 10A constituting a lower surface of the soldering apparatus 100. Furthermore, the main frame 10 has inner columns 10C erected above the transfer rails 13A, 13B from the lower inner frames 10B, and pedestals 10D supported from below on the inner columns 10C. The pedestals 10D are provided above the transfer rails 13A, 13B.

As shown in FIG. 4, at the upper part of the main frame 10, operation display units 71 for allowing an operator to input various settings is provided. In the present embodiment, two personal computers 71A, 71B are arranged on the upstream side of the transfer rails 13B as the operation display units 71. The personal computer 71A is used to set drive control settings such as the transfer speed of the transfer rails 13A and the temperature setting and air volume setting in the muffle 20A, and the personal computer 71B is used to set drive control settings such as the transfer speed of the transfer rails 13B and the temperature setting and air volume setting in the muffle 20B. The display screen of the personal computer 71A displays the settings and driving conditions on the muffle 20A side, and the display screen of the personal computer 71B displays the settings and driving conditions on the muffle 20B side.

As shown in FIGS. 2 and 3, the upstream end and downstream end of the transfer rails 13A, 13B are provided on the main frame 10 and they extend in parallel from the board-charging port 11 to the board carrying-out port 12. The transfer rails 13A, 13B transfer the printed circuit boards P1, P2 charged into the soldering apparatus 100 from the board-charging port 11 in an arrow direction in FIG. 2 and transfer them out of the soldering apparatus 100 from the board carrying-out port 12. A pair of the transfer rails 13A supports the lower surface and side surface of the printed circuit board P1 and transfers it at a predetermined speed, and a pair of the transfer rails 13B supports the lower surface and side surface of the printed circuit board P2 and transfers it at the predetermined speed. As the transfer rails 13A, 13B, it is preferable to use pairs of rails that can be adjusted in width in accordance with the width of the printed circuit boards P1, P2 to be transferred. In the present embodiment, the widths of the transfer rails 13A, 13B can be respectively adjusted independently by rail width adjustment parts 41A provided at the upstream end and downstream end of the main frame 10.

The rail width adjustment parts 41A adjust the widths of the transfer rails 13A, 13B according to the widths of the printed circuit boards P1, P2 input by the operator using the operation display units 71. Specifically, in the rail width adjustment parts 41A, screws are respectively formed corresponding to the transfer rails 13A, 13B, and the transfer rails 13A, 13B are respectively screwed on these screw shafts. Between the pair of the transfer rails 13A, the one is fixed, and the other moves according to the rotation of the screw shaft, whereby the width of the transfer rails 13A can be narrowed or widened. Also between the pair of the transfer rails 13B, the one is fixed, and the other moves according to the rotation of the screw shaft, whereby the width of the transfer rails 13B can be narrowed or widened.

Returning back to FIG. 1, the muffle 20A has an upper muffle 20 a as an upper main body and a lower muffle 20 b as a lower main body. The upper muffle 20 a and the lower muffle 20 b are provided at positions vertically sandwiching the transfer rails 13A along the transfer rails 13A. The muffle 20B has an upper muffle 20 c as an upper main body and a lower muffle 20 d as a lower main body. The upper muffle 20 c and the lower muffle 20 d are provided at positions vertically sandwiching the transfer rails 13B along the transfer rails 13B. In the muffles 20A, 20B, an inert gas such as nitrogen gas (N2) may sometimes be supplied as an atmosphere gas to suppress the oxidation of the solder. As will be described in detail later, the muffle 20A is opened/closed by lifting/lowering the upper muffle 20 a by the operation of the opening/closing part 30A. In addition, the muffle 20B is opened/closed by lifting/lowering the upper muffle 20 c by the operation of the opening/closing part 30B.

A heat insulating member 21 a is provided around the upper muffle 20 a, and a heat insulating member 21 b is provided around the lower muffle 20 b. The heat insulating member 21 a covers the upper surface and side surface of the upper muffle 20 a, and the heat insulating member 21 b covers the lower surface and side surface of the lower muffle 20 b. By covering the periphery of the muffle 20A with the heat insulating members 21 a and 21 b, the temperature interference from the outside of the muffle 20A to the inside of the muffle 20A is suppressed. That is, the muffle 20A is not influenced by the temperature setting in each zone in the muffle 20B.

A heat insulating member 21 c is provided around the upper muffle 20 c, and a heat insulating member 21 d is provided around the lower muffle 20 d. The heat insulating member 21 c covers the upper surface and side surface of the upper muffle 20 c, and the heat insulating member 21 d covers the lower surface and side surface of the lower muffle 20 d. By covering the periphery of the muffle 20B with the heat insulating members 21 c and 21 d, the temperature interference from the outside of the muffle 20B to the inside of the muffle 20B is suppressed. That is, the muffle 20B is not influenced by the temperature setting in each zone in the muffle 20A.

As shown in FIG. 5A, the lower muffle 20 b is provided with an elastic member 24 at a position where it is sandwiched between the upper muffle 20 a and the lower muffle 20 b and is in contact with them. The lower muffle 20 d is provided with an elastic member 24 at a position where it is sandwiched between the upper muffle 20 c and the lower muffle 20 d and is in contact with them. Each of the elastic members 24 is elongated and is provided from the upstream end to the downstream end of the muffles 20A, 20B. The elastic members 24 may be provided on the upper muffles 20 a, 20 c, but in the present embodiment, two rows of the elastic members 24 are provided on adjacent edges of the lower muffles 20 b, 20 d, and three rows of the elastic members 24 are provided on mutually distant edges of the lower muffles 20 b, 20 d. The elastic members 24 suppress positional deviation of the upper muffles 20 a, 20 c and the lower muffles 20 b, 20 d by opening/closing of the muffles 20A, 20B, and keep airtightness in the muffles 20A, 20B.

The opening/closing part 30A includes cylinders 31A as first lifting/lowering means for lifting/lowering the upper muffle 20 a and a drive mechanism (not shown) for driving the cylinders 31A, and further includes a sub-frame 32A to which the cylinders 31A are attached below and an upper cover 33A provided above the sub-frame 32A to cover the upper side and lateral side of the upper muffle 20 a.

The opening/closing part 30B includes cylinders 31B as second lifting/lowering means for lifting/lowering the upper muffle 20 c and a drive mechanism (not shown) for driving the cylinder 31B, and further includes a sub-frame 32B to which the cylinders 31B are attached below and an upper cover 33B provided above the sub-frame 32B to cover the upper side and lateral side of the upper muffle 20 c.

As shown in FIG. 3, four cylinders 31A, 31B are respectively arranged on the pedestal 10D. In the present embodiment, the two cylinders 31A are arranged on the pedestal 10D on the upstream side of the transfer rails 13A, and the two cylinders 31A are arranged on the pedestal 10D on the downstream side of the transfer rails 13A. The two cylinders 31B are arranged on the upstream side of the pedestal 10D on the transfer rails 13B, and the two cylinders 31B are arranged on the pedestal 10D on the downstream side of the transfer rails 13B. As described above, the pedestals 10D avoid the transfer rails 13A, 13B by being supported by the inner columns 10C which are erected above the transfer rails 13A, 13B from the lower side of the main frame 10. Therefore, the cylinders 31A are provided above the transfer rails 13A while avoiding the transfer rails 13A, and the cylinders 31B are provided above the transfer rails 13B while avoiding the transfer rails 13B. Multistage electric cylinders are used as the cylinders 31A, 31B of the present embodiment.

As shown in FIG. 5A, the sub-frame 32A is provided above the upper muffle 20 a. The upper muffle 20 a and the sub-frame 32A are screwed via the heat insulating member 21 a, and the sub-frame 32A and the upper cover 33A are screwed. As a result, when the cylinders 31A extend/retract in the vertical direction, the upper muffle 20 a, the sub-frame 32A and the upper cover 33A integrally lift/lower, and the muffle 20A is opened/closed by the opening/closing part 30A.

Specifically, when the cylinders 31A extend upward, the sub-frame 32A is pushed upward, so that the upper muffle 20 a and the upper cover 33A are also pushed upward, and the muffle 20A is opened. When the cylinders 31A retract downward, the sub-frame 32A is pulled downward, so that the upper muffle 20 a and the upper cover 33A are also pulled downward, and the muffle 20A is closed.

The sub-frame 32B is provided above the upper muffle 20 c. The upper muffle 20 c and the sub-frame 32B are screwed via the heat insulating member 21 c, and the sub-frame 32B and the upper cover 33B are screwed. Accordingly, when the cylinders 31B extend/retract in the vertical direction, the upper muffle 20 c, the sub-frame 32B, and the upper cover 33B integrally lift/lower, and the muffle 20B is opened/closed by the opening/closing part 30B.

Specifically, when the cylinders 31B extend upward, the sub-frame 32B is pushed upward, so that the upper muffle 20 c and the upper cover 33B are also pushed upward, and the muffle 20B is opened. When the cylinders 31B retract downward, the sub-frame 32B is pulled downward, so that the upper muffle 20 c and the upper cover 33B are also pulled downward, and the muffle 20B is closed. The cylinders 31A, 31B extend/retract by a predetermined height h, for example, 400 mm to open and close the muffles 20A, 20B.

As shown in FIG. 4, the main frame 10 has an upstream side intrusion-preventing plate 10E erected from the main frame 10 on the upstream side of the upper covers 33A and 33B, and a downstream side intrusion-preventing plate 10F erected from the main frame 10 on the downstream side of the upper covers 33A and 33B. As shown in FIG. 5B, the upstream side intrusion-preventing plate 10E has the same shape as a combined shape of the side surfaces on the upstream side of the upper covers 33A and 33B. With the muffles 20A, 20B closed, the upstream side intrusion-preventing plate 10E contacts the side surfaces on the upstream side of the upper covers 33A and 33B. The upstream side intrusion-preventing plate 10E is provided above the board-charging port 11 so that the inside of the muffle 20A is not visible from the upstream side of the muffle 20A even in the state where the upper cover 33A is open, thereby suppressing the intrusion of foreign matter from the upstream side of the muffle 20A into the muffle 20A. Although not shown, the upstream side intrusion-preventing plate 10E prevents the inside of the muffle 20B from being visible from the upstream side of the muffle 20B even in the state where the upper cover 33B is open, thereby suppressing the intrusion of foreign matter from the upstream side of the muffle 20B into the muffle 20B.

Although not shown, the downstream side intrusion-preventing plate 10F has the same shape as a combined shape of the side surfaces on the downstream side of the upper covers 33A and 33B. With the muffles 20A, 20B closed, the downstream side intrusion-preventing plate 10F contacts the side surfaces on the downstream side of the upper covers 33A and 33B. The downstream side intrusion-preventing plate 10F is provided above the board carrying-out port 12 so that the inside of the muffles 20A, 20B is not visible from the downstream side of the muffles 20A, 20B even in the state where the upper cover 33A or the upper cover 33B is opened, thereby suppressing the intrusion of foreign matter from the downstream side of the muffles 20A, 20B into the muffles 20A, 20B.

As shown in FIG. 6, the control unit 70 is connected to the transfer rails 13A, 13B, the drive mechanisms (not shown) for driving the cylinders 31A, 31B, the heaters 7, the heaters 8, the cooling fans 9, the operation display units 71 and a memory unit 72. When the operator operates the operation display units 71, the control unit 70 controls the transfer speed of the transfer rails 13A, 13B, the timing to transfer the printed circuit boards P1, P2, the timing to extend/retract the cylinders 31A, 31B, the temperatures of the heaters 7 and the heaters 8, the ON/OFF of the cooling fans 9, and the like. The memory unit 72 stores information input at the operation display units 71, an instruction of the control unit 70, an operation time of the soldering apparatus 100, and the like.

Subsequently, an operation example of the soldering apparatus 100 will be described. It is premised that the control unit 70 operates each unit according to various settings input by the operator.

As shown in FIG. 4, the operator starts the soldering apparatus 100 and performs various settings of the soldering apparatus 100 at the operation display units 71. Specifically, he or she operates the personal computer 71A to input, for example, the width of the printed circuit board P1 and the temperature settings in the muffle 20A, and operates the personal computer 71B to input, for example, the width of the printed circuit board P2 and the temperature setting in the muffle 20B for performing various settings.

As shown in FIG. 6, the control unit 70 drives the respective units of the soldering apparatus 100 according to the various settings input by the operation display units 71. The screw shaft of the rail width adjustment part 41A is driven so that the transfer rails 13A move so as to fit the width of the printed circuit board P1, and that the transfer rails 13B move so as to fit the width of the printed circuit board P2. The heaters 7 and the heaters 8 are heated to a predetermined temperature, and the cooling fans 9 are driven.

The transfer rails 13A, 13B transfer the printed circuit boards P1, P2 from the board-charging port 11 to the board carrying-out port 12 in the arrow direction shown in FIG. 2. When the printed circuit boards P1, P2 on which an electronic component for surface mounting is mounted are placed on the transfer rails 13A, 13B, they are carried from the board-charging unit 14 into the main frame 10. Furthermore, the printed circuit board P1 enters the muffle 20A, and the printed circuit board P2 enters the muffle 20B. In the preheating zone 17 of each muffle, the heat of the heaters 7 activates the flux applied to the printed circuit boards P1, P2, and removes the oxide film on the surfaces of the electrodes and the solder paste. Subsequently, when the printed circuit boards P1, P2 are transferred to the main heating zone 18 of each muffle, the solder is melted by the heat of the heaters 8. When the printed circuit boards P1, P2 are transferred to the cooling zone 19 of each muffle, the printed circuit boards P1, P2 are cooled and the electronic components are fixed to the electrodes of the printed circuit boards P1, P2. The printed circuit board P1 cooled in the cooling zone 19 exits the muffle 20A, and the cooled printed circuit board P2 exits the muffle 20B. Furthermore, the printed circuit boards P1, P2 are carried out of the main frame 10 from the board carrying-out port 12.

For example, when desiring to open the muffle 20A for maintenance within the muffle 20A, the operator operates the personal computer 71A to stop the drive of the transfer rails 13A and within the muffle 20A and to open the muffle 20A. Since there is no need to open the muffle 20B at this time, the drive of the transfer rails 13B and within the muffle 20B may be continued, and the soldering of the printed circuit board P2 may be continued.

When the control unit 70 receives the instruction to open the muffle 20A, the control unit 70 stops the drive of the transfer rails 13A and within the muffle 20A. When the drive of the transfer rails 13A and the muffle 20A stops, the control unit 70 drives the drive mechanism (not shown) for the cylinders 31A. As shown in FIG. 5A, when the cylinders 31A extend upward, the sub-frame 32A is pushed upward by the cylinders 31A so that the upper muffle 20 a and the upper cover 33A are also pushed upward together, and the muffle 20A opens by the height h.

The operator is able to perform maintenance within the muffle 20A when the muffle 20A opens. As shown in FIG. 5B, in the state where the muffle 20A opens, the upstream side intrusion-preventing plate 10E prevents an object from intruding into the muffle 20A from the upstream side of the muffle 20A, and the downstream side intrusion-preventing plate 10F prevents an object from intruding into the muffle 20A from the downstream side of the muffle 20A. Due to the presence of the upstream side intrusion-preventing plate 10E and the downstream side intrusion-preventing plate 10F, no maintenance is performed from the lateral sides on the upstream side and the downstream side of the muffle 20A, but maintenance is performed from the lateral side opposite to the position of the muffle 20B to the muffle 20A, as shown by the arrow A4.

When the maintenance is completed, the operator operates the personal computer 71A to close the muffle 20A and to drive the transfer rails 13A and the inside of muffle 20A. When the control unit 70 receives the instruction to close the muffle 20A, the control unit 70 drives the drive mechanism (not shown) for the cylinders 31A. When the cylinders 31A retract downward, the sub-frame 32A is pulled downward, so that the upper muffle 20 a and the upper cover 33A are also pulled downward together, and the muffle 20A is closed. When the muffle 20A is closed, the control unit 70 restarts the drive of the transfer rails 13A and within the muffle 20A and restarts the soldering of the printed circuit board P1.

Although not shown, when it is desired to open the muffle 20B for maintenance within the muffle 20B, it is possible to perform the same operation as that of opening the muffle 20A. First, the operator operates the personal computer 71B to stop the drive of the transfer rails 13B and within the muffle 20B and to open the muffle 20B. At this time, since it is not necessary to open the muffle 20A, the drive of the transfer rails 13A and within the muffle 20A may be continued, and the soldering of the printed circuit board P1 may be continued.

When the control unit 70 receives the instruction to open the muffle 20B, the control unit 70 stops the drive of the transfer rails 13B and within the muffle 20B. When the drive of the transfer rails 13B and within the muffle 20B stops, the control unit 70 drives the drive mechanism (not shown) for the cylinders 31B. When the cylinders 31B extend upward, the sub-frame 32B is pushed upward by the cylinders 31B, so that the upper muffle 20 c and the upper cover 33B are also pushed upward together, and the muffle 20B opens by the height h.

The operator is able to perform maintenance within the muffle 20B when the muffle 20B opens. In the state where the muffle 20B opens, the upstream side intrusion-preventing plate 10E prevents an object from intruding into the muffle 20B from the upstream side of the muffle 20B, and the downstream side intrusion-preventing plate 10F prevents an object from intruding into the muffle 20B from the downstream side of the muffle 20B. Due to the presence of the upstream side intrusion-preventing plate 10E and the downstream side intrusion-preventing plate 10F, no maintenance is performed from the lateral sides on the upstream side and the downstream side of the muffle 20B, but maintenance is performed from the lateral side opposite to the position of the muffle 20A to the muffle 20B, as shown by the arrow A5 in FIG. 5B.

When the maintenance is completed, the operator operates the personal computer 71B to close the muffle 20B and to drive the transfer rails 13B and the inside of muffle 20B. When the control unit 70 receives the instruction to close the muffle 20B, the control unit 70 drives the drive mechanism (not shown) for the cylinders 31B. When the cylinders 31B retract downward, the sub-frame 32B is pulled downward, so that the upper muffle 20 c and the upper cover 33B are also pulled downward together, and the muffle 20B is closed. When the muffle 20B is closed, the control unit 70 restarts the drive of the transfer rails 13B and within the muffle 20B and restarts the soldering of the printed circuit board P2.

In the present embodiment, the main frame 10 is provided with the opening/closing part 30A for opening/closing the muffle 20A and the opening/closing part 30B for opening/closing the muffle 20B, in the soldering apparatus 100, so the muffle 20A and the muffle 20B can be opened/closed separately. Therefore, even when the one muffle is opened, it is possible to prevent the exposure of the inside of the other muffle. Specifically, it is possible to prevent the inside of the muffle 20B from being exposed when the muffle 20A is opened, and to prevent the inside of the muffle 20A from being exposed when the muffle 20B is opened. Furthermore, independently different temperature profiles can be respectively set for the muffle 20A and the muffle 20B. Therefore, even when either one of the muffles is open, the soldering operation can be continued in the other muffle, and, besides, the set temperature profile can be kept in the other muffle without being affected by the temperature in the one muffle. Of course, both the muffles 20A, 20B can be opened according to need.

Since the soldering apparatus 100 includes the muffles 20A, 20B in the main frame 10, soldering can be performed in both the muffles 20A, 20B, so that a large amount of soldering can be efficiently performed as compared with a single rail type soldering apparatus. In addition, the production cost reduction and space saving of the soldering apparatus can be realized as compared with the case where two conventional soldering apparatuses are arranged in parallel. In the soldering apparatus 100, different products may be produced at the same time by transferring the printed circuit board P1 using the transfer rails 13A and transferring the printed circuit board P2 using the transfer rails 13B, or the same printed circuit board may be carried using the transfer rails 13A, 13B.

The configurations of the respective zones in the muffles 20A, 20B are not limited to those described above, and various zone configurations are conceivable. For example, the numbers of the preheating zones, main heating zones and cooling zones are not limited to the numbers of the zones described above, and a vacuum degassing zone for vacuum degassing the heated printed circuit boards P1, P2 may be provided. When the printed circuit boards P1, P2 are transferred by intermittent feeding, a buffering zone may be provided to secure a predetermined time in the zone before the intermittent feeding of any of the printed circuit boards P1, P2. Further, the configurations of the zones in the muffle 20A and the muffle 20B are the same in the present embodiment, but mutually different zone configurations may be used.

The configuration and operation of the rail width adjustment parts 41A are not limited to the above-described embodiment. The operator may operate a screw adjustment member (not shown) to rotate the screw shafts of the rail width adjustment parts 41A to change the widths of the transfer rails 13A, 13B. The widths of the transfer rails 13A, 13B are respectively configured to have been independently adjusted, but, when the printed circuit boards P1, P2 have the same width, they may be interlocked so that the rail widths of the printed circuit boards P1, P2 are the same. In addition, the transfer rails 13A, 13B may be provided with a warpage preventing mechanism for preventing the warpage of the printed circuit boards P1, P2.

In the soldering apparatus 100 of the present embodiment, the preheating zone 17, the main heating zone 18 and the cooling zone 19 are provided in each of the muffles 20A, 20B, and the heaters 7 and 8 and the cooling fans 9 are provided in each of the muffles 20A, 20B. Briefly, the soldering apparatus 100 includes the heaters 7 and 8 and the cooling fans 9 corresponding to the printed circuit boards P1, P2, respectively. Therefore, as compared with the configuration in which the printed circuit boards P1, P2 are transferred within one case and heated or cooled collectively, the soldering apparatus 100 can uniformly heat or cool each of the printed circuit boards P1, P2.

In the soldering apparatus 100 of the present embodiment, the upper muffles 20 a, 20 c are lifted/lowered by the cylinders 31A, 31B in the vertical direction, without being rotated relative to the lower muffles 20 b, 20 d, to be opened/closed. Therefore, for the operator who checks the inside of the muffle 20A from the arrow A4 side in FIG. 5B in the state where the muffle 20A opens, the entire muffle 20A becomes visible without preventing the narrowing of the side near the muffle 20B within the muffle 20A, i.e., the back side for the operator. Further, for the operator who checks the inside of the muffle 20B from the arrow A5 side, the entire muffle 20B becomes visible without preventing the narrowing of the side near the muffle 20A within the muffle 20B, i.e., the back side for the operator.

The muffles 20A, 20B are not limited to the embodiment in which they are lifted/lowered to be opened/closed. For example, the upper muffles 20 a, 20 c may rotate respectively around the vicinities on the sides to which the upper muffles 20 a, 20 c are adjacent as fulcrums, and may be opened/closed by the operators who are located on the sides of the arrows A4 and A5. Further, the present invention is not limited to the embodiment in which the upper cover 33A is attached to the sub-frame 32A and the upper cover 33B is attached to the sub-frame 32B. The upper cover 33A may be opened/closed separately from the muffle 20A and the sub-frame 32A, and the upper cover 33B may be opened/closed separately from the muffle 20B and the sub-frame 32B.

The lifting/lowering means are not limited to the cylinders 31A, 31B. Non-multistage cylinders may be used as the lifting/lowering means. FIG. 7 shows a non-multistage cylinder 31C in a retracted state and an extended state, and a multistage cylinder 31A, 31B in a retracted state and an extended state in this order from the left. When the using non-multistage cylinders 31C to be extended/retracted by the predetermined height h, for example, 400 mm, the cylinders 31C may have to have at least a height of 400 mm, which is equal to the height h, even in the case where the muffles 20A, 20B are closed by retracting the cylinders 31C. On the other hand, it suffices that the multistage cylinders 31A, 31B may have a height of about 200 mm, which is half the height h, in the state where the muffles 20A, 20B are closed by retracting the cylinders.

Therefore, the soldering apparatus 100 can achieve space saving in the height direction in the state where the muffles 20A, 20B are closed by using the cylinders 31A, 31B. As the lifting/lowering means, other means that can be driven to extend/retract by oil pressure, air pressure, water pressure or the like can be used. Further, four cylinders 31A, 31B are arranged in the present embodiment, but the present invention is not limited to this. Four or more cylinders 31A, 31B may be provided, or the numbers of the cylinders 31A and 31B may be different from each other. In addition, when the upper muffles 20 a, 20 c rotate and open/close, the cylinders 31A, 31B may be arranged in one row on a side near the operator.

In the present embodiment, by providing the operation display units 71 at one place, even if there is only one operator for operating or confirming the operation display units 71, the operator does not have to move between the positions of the personal computer 71A and the personal computer 71B. Although two personal computers 71A, 71B are arranged on the upstream side of the transfer rails 13B, the present invention is not limited to this. The operation display units 71 may be provided on the side of the transfer rails 13A, or may be provided on the downstream side of the transfer rails 13A, 13B. In addition, various settings of the transfer rails 13A, 13B and within the muffles 20A, 20B may be performed by one operation display unit, or an operation unit of the touch panel system and a display unit such as a liquid crystal panel or an organic EL panel may be integrally combined for use. Various settings of the transfer rails 13A and the transfer rails 13B, within the muffle 20A and within the muffle 20B and the like by the operation display units 71 may be identical or different in contents.

In addition, the muffles 20A, 20B may be opened/closed by a button (not shown) provided separately from the operation display units 71. At this time, for safety, it is preferable that the muffle 20A or the muffle 20B be opened/closed by pressing two buttons simultaneously. In addition, for example, if the button for opening/closing the muffle 20A and the button for opening/closing the muffle 20B are different from each other, or if a dial or the like for switching the opening/closing of the muffles 20A, 20B is provided, an erroneous operation as to which of the muffles 20A, 20B should be opened/closed can be suppressed.

INDUSTRIAL APPLICABILITY

The present invention is very suitably applied to a soldering apparatus for soldering a printed circuit board, and, especially, to a reflow device for heating and soldering a printed circuit board on which a surface mounted component(s) is (are) mounted.

EXPLANATION OF CODES

-   P1, P2: Printed Circuit Board -   10: Main Frame -   11: Board-charging Port -   12: Board carrying-out Port -   13A: Transfer Rails (First Transfer Means) -   13B: Transfer Rails (Second Transfer Means) -   14: Board-charging Unit -   16: Board Carrying-out Part -   17: Preheating Zone -   18: Main Heating Zone -   19: Cooling Zone -   20A: Muffle (First Reflow Furnace Main Body) -   20B: Muffle (Second Reflow Furnace Main Body) -   20 a, 20 c: Upper Muffle (Upper Main Body) -   20 b, 20 d: Lower Muffle (Lower Main Body) -   30A: Opening/closing Part (First Opening/closing Means) -   30B: Opening/closing part (Second Opening/closing Means) -   31A: Cylinders (First Lifting/lowering Means) -   31B: Cylinders (Second Lifting/lowering Means) -   70: Control Unit -   100: Soldering Apparatus 

The invention claimed is:
 1. A soldering apparatus comprising: first transfer rails for transferring a first printed circuit board; second transfer rails provided in parallel to a transfer direction of the first printed circuit board transferred by the first transfer rails; a first reflow furnace main body for heating the first printed circuit board transferred by the first transfer rails; a second reflow furnace main body for heating a second printed circuit board transferred by the second transfer rails; a frame for housing the first reflow furnace main body and the second reflow furnace main body, wherein the frame contains a first opening/closing part for opening/closing the first reflow furnace main body vertically and a second opening/closing part for opening/closing the second reflow furnace main body vertically, and wherein the first reflow furnace main body and the second reflow furnace main body are opened/closed separately; a first pedestal within the first reflow furnace main body; and a second pedestal within the second reflow furnace main body, wherein each of the first and second reflow furnace main bodies is configured to have an upper main body and a lower main body, wherein the first opening/closing part includes a first lifting/lowering part for lifting/lowering the upper main body of the first reflow furnace main body vertically, without being rotated relative to the lower main body of the first reflow furnace main body, wherein the second opening/closing part includes a second lifting/lowering part for lifting/lowering the upper main body of the second reflow furnace main body vertically, without being rotated relative to the lower main body of the second reflow furnace main body, wherein the first lifting/lowering part is arranged on the first pedestal and above the first transfer rails within the first reflow furnace main body and positioned to push upward on the upper main body of the first reflow furnace main body, wherein the second lifting/lowering part is arranged on the second pedestal and above the second transfer rails within the second reflow furnace main body and positioned to push upward on the upper main body of the second reflow furnace main body, and wherein the first pedestal is provided above the first transfer rails and the second pedestal is provided above the second transfer rails.
 2. The soldering apparatus according to claim 1, wherein the first lifting/lowering part is arranged while avoiding the first transfer rails; and wherein the second lifting/lowering part is arranged while avoiding the second transfer rails.
 3. The soldering apparatus according claim 1, wherein the first lifting/lowering part and the second lifting/lowering part include multistage cylinders.
 4. The soldering apparatus according to claim 1, wherein the lower main body of the first reflow furnace main body is provided with an elastic member at a position where the elastic member is sandwiched between the upper main body and the lower main body of the first reflow furnace main body and is in contact with them, and wherein the lower main body of the second reflow furnace main body is provided with another elastic member at a position where the elastic member is sandwiched between the upper main body and the lower main body of the second reflow furnace main body and is in contact with them.
 5. The soldering apparatus according to claim 1, wherein the first opening/closing part includes a first upper cover that covers an upper side and a lateral side of the upper main body of the first reflow furnace main body, wherein the second opening/closing part includes a second upper cover that covers an upper side and a lateral side of the upper main body of the second reflow furnace main body, and wherein the frame has an upstream side intrusion-preventing plate that is erected from the frame on an upstream side of the first upper cover and the second upper cover with respect to a transfer direction of any of the first and second printed circuit boards and a downstream side intrusion-preventing plate that is erected from the frame on a downstream side of the first upper cover and the second upper cover with respect to the transfer direction of any of the first and second printed circuit boards.
 6. The soldering apparatus according to claim 1, wherein an upstream end and a downstream end of the first transfer rails along the transfer direction of the first printed circuit board are provided on the frame; and wherein an upstream end and a downstream end of the second transfer rails along the transfer direction of the second printed circuit board are also provided on the frame.
 7. The soldering apparatus according to claim 1, wherein a plurality of heat-insulating members are provided, respectively, around the first reflow furnace main body and the second reflow furnace main body.
 8. The soldering apparatus according to claim 1, wherein the first reflow furnace main body and the second reflow furnace main body each respectively include a preheating zone for preheating the respective first printed circuit board and second printed circuit board, a main heating zone for soldering the preheated respective first printed circuit board and second printed circuit board, and a cooling zone for cooling the soldered respective first printed circuit board and second printed circuit board.
 9. The soldering apparatus according to claim 1, wherein the first and second pedestals are supported by columns which are erected above the first and second transfer rails from a lower side of the frame. 